Fresh off a primary in which dark-money attacks were launched against any Republican who stood in Ducey's way, we now learn that Ducey has been cozying up to America's premier princes of dark money.

Secret tapes released last week by The Nation reveal that Ducey was courting billionaire industrialists Charles and David Koch and their network of mega donors at their annual secret summit in June – and not for the first time.

"I have been coming to this conference for years," he told the billionaires in attendance. "It's been very inspirational."

Inspirational, no doubt, and highly profitable for a guy with political aspirations.

While Ducey is the state's treasurer, most Arizonans had no idea who he was until 2012 when he chaired the drive to kill Proposition 204, aimed at establishing a permanent sales tax for public education.

A dark-money group called Americans for Responsible Leadership donated $925,000 to Ducey's $1.8 million campaign against Prop. 204 – elevating Ducey's profile even as it killed the sales tax proposal.

Thanks to Internal Revenue Service records, we now know that Americans for Responsible Leadership — which spent another $575,000 to kill the top-two primary initiative -- was funded almost wholly by the Koch brothers conservative network.

Ducey's campaign isn't talking about how he came to be kissing up to the Kochs at the June summit, held at a Dana Point, Calif., resort. Or how much money the Kochs and their pals might have committed to the push to get him the governor's job.

"Doug has taken his message of greater opportunity to every corner of the state, in addition to communicating that vision outside Arizona," spokeswoman Melissa DeLaney said, via e-mail. "As a candidate for governor, Doug has attended events hosted by individuals of varied political persuasions where policy issues were debated, and as governor, he will be an advocate for all Arizonans."

An advocate for all Arizonans... So says the candidate who is quietly hanging with billionaires who seem intent, among other things, on privatizing education, killing unions and eliminating government regulations that protect the air we breathe.

Politicos assure me that Ducey's really a centrist who will stand up to the GOP's crazy contingent at the Legislature. Yet the Center for Arizona Policy's Cathi Herrod sits on his kitchen cabinet and now he's hobnobbing with the sons of one of the founders of the John Birch Society.

Well, as Ducey said at that Koch summit, "You're known by the company you keep."

Lately, the company he's keeping seems all about covert cash and corporate special interests.

No anonymous donors have shelled out cash to get Democrat Fred DuVal elected.

Meanwhile, millions of dollars from anonymous interests were spent to ensure that Ducey won the Republican nomination. And American Encore, part of the Kochs' dark-money web, has spent spent $1.3 million in the general-election race, touting Ducey and attacking DuVal.

With more to come before the Nov. 4 election. Much more, I'd bet.

As Ducey told his secret pals, the ones who are in the market to install their guys in governor's offices across the country: